1. Field of the Invention
The present invention relates to an apparatus for delivery of a predetermined volume of lead to a mould and in particular, but not exclusively, to such apparatus for use in manufacturing cast on straps during the manufacture of batteries.
2. Description of the Related Art
In the manufacture of batteries, particularly for example lead acid batteries, it is known to cast straps and other formations onto the lugs of battery plates so as to, for example, form a connection between a set of plates within a cell of the battery. Such straps are generally cast by filling a mould cavity with lead and dipping lugs into the cavity prior to the cooling of the lead. Typically, the mould cavities are filled by allowing lead to flow into channels at the sides of the cavities and spill over a weir into the mould. An example of such a moulding apparatus is shown in the Applicant's earlier application WO94/16466. In order to ensure a good connection between the lugs and casting, the lead must remain hot until the lugs are in position. However, in order to minimize cycle time in production, the lead must be cooled as quickly as possible once the plates are in position.
It is important that the volume of lead is carefully controlled during strap casting as excess lead (for example as a result of mould features such as weirs) will have an impact on both the cost and weight of the final battery produced.